This invention relates to novel methods of judging mouth odor. More particularly, it relates to a method of judging mouth odor wherein the odor of cultured saliva obtained by collecting saliva immediately after wake-up and culturing it under anaerobic conditions is employed as the mouth odor, and another method of judging mouth odor wherein anaerobic bacteria contained in collected saliva are counted.
With the recent preference to cleanliness, people worrying about their own body odor, mouth odor and the like have been increasing. Mouth odor ranks second among these offensive odors following body odor. According to questionnaire data, mouth odor is not so strong in young people but becomes more and more noticeable with aging.
In general, mouth odor has a broad meaning including all offensive smells generating from the mouth, for example, smells simply generating from smelling foods remaining in the mouth and smells caused by systemic diseases.
As major components of mouth odor, hydrogen sulfide, methyl mercaptane and dimethyl disulfide may be cited. These sulfur-containing compounds are main factors causative of mouth odor. It is considered that the strength of mouth odor relate to these three sulfur-containing compounds. Accordingly, studies have been made on mouth odor and prevention thereof by using these three compounds.
However, hydrogen sulfide is in the form of a gas at ordinary temperature while an aqueous solution or a solution in a solvent of methyl mercaptane should be prepared in situ because of its very low boiling point. Therefore, it takes a lot of trouble to prepare an artificial mouth odor by using these compounds. Although various odor-collection methods have been proposed so far to analyze mouth odor, there are few methods which can be carried out while loading little burden on subjects.
To judge mouth odor, it has been a practice to analyze the mouth odor by sensory tests or gas chromatography. Because of depending on human olfactory perception, sensory tests suffer from some problems such as olfactory fatigue, difficulties in numerical indication and poor reproducibility. Although gas chromatography is superior in objectivity, troublesome operations are needed in collecting and analyzing odor by this method. Moreover, gas chromatography has an additional problem of being restricted in the test site.
To collect mouth odor, use has been recently made of a portable sulfide monitor and the like by which volatile sulfur-containing compounds can be perceived in the oral cavity. In this method, however, a number of burdens (resting quietly before the measurement, being provided with a plastic tube for feeding air, breathing through the nose while keeping his/her mouth open, etc.) are loaded on a subject. Thus, this method is not applicable to those who cannot breathe through the nose. In this case, furthermore, trouble some operations should be performed by an operator.
Accordingly, an object of the invention is to provide a convenience method of judging mouth odor by using an artificial mouth odor prepared by a convenient method.
In order to achieve the above object, the inventors have conducted extensive studies. As a result, they have successfully found out that mouth odor can be very excellently judged by culturing saliva immediately after wake-up under anaerobic conditions and using the head space components of the cultured saliva thus obtained as an artificial mouth odor without resort to any troublesome operations to be carried out by the operator for preparing an artificial mouth odor and without loading any burdens to the subject; and that the anaerobic bacterial count in the saliva thus collected correlates to the components detected therefrom and thus mouth odor can be very excellently judged by counting the anaerobic bacteria without loading any burdens to the operator or subject. The invention has been completed based on these findings.
Accordingly, the invention relates to a method of judging mouth odor characterized by culturing saliva immediately after wake-up under anaerobic conditions and analyzing the head space components of the cultured saliva thus obtained, and another method of judging mouth odor characterized by counting anaerobic bacteria contained in the collected saliva.